U.S. patent application number 12/097117 was filed with the patent office on 2009-12-03 for paint compositions, a method of paint finishing and painted objects.
This patent application is currently assigned to BASF COATINGS JAPAN LTD.. Invention is credited to Takehito Ito, Tetsu Konishi, Shinji Mitsumune, Rui Nimi, Hiroyuki Tagkagi.
Application Number | 20090299016 12/097117 |
Document ID | / |
Family ID | 37872283 |
Filed Date | 2009-12-03 |
United States Patent
Application |
20090299016 |
Kind Code |
A1 |
Konishi; Tetsu ; et
al. |
December 3, 2009 |
PAINT COMPOSITIONS, A METHOD OF PAINT FINISHING AND PAINTED
OBJECTS
Abstract
Disclosed herein is a paint composition comprising a hydroxyl
group containing resin (A), comprising structural units based on
2,2-dimethylolalkanoic acid, having a hydroxyl group value of from
200 to 400 mgKOH/g, and comprising less than 25 weight % in the
resin solid fraction of structural units based on a lactone
compound; a hydroxyl group containing resin (B), having a hydroxyl
group value from 50 to 200 mgKOH/g, and comprising from 25 to 75
weight % in the resin solid fraction of structural units based on a
lactone compound; and a crosslinking agent (C) comprising at least
two OH-reactive functional groups per molecule; wherein the resin
solid fraction weight ratio (A)/(B) of the hydroxyl group
containing resin (A) and the hydroxyl group containing resin (B) is
from 90/10 to 10/90.
Inventors: |
Konishi; Tetsu; (Kanagawa,
JP) ; Mitsumune; Shinji; (Kanagawa, JP) ;
Tagkagi; Hiroyuki; (Yokohama, JP) ; Ito;
Takehito; (Tokyo, JP) ; Nimi; Rui; (Munster,
DE) |
Correspondence
Address: |
Mary E. Golota;Cantor Colburn LLP
201 W. Big Beaver Road, Suite 1101
Troy
MI
48084
US
|
Assignee: |
BASF COATINGS JAPAN LTD.
Yokohama-shi
JP
|
Family ID: |
37872283 |
Appl. No.: |
12/097117 |
Filed: |
November 1, 2006 |
PCT Filed: |
November 1, 2006 |
PCT NO: |
PCT/IB2006/003197 |
371 Date: |
July 30, 2009 |
Current U.S.
Class: |
525/450 |
Current CPC
Class: |
C08L 2312/00 20130101;
C09D 133/066 20130101; C08L 33/066 20130101; C08L 2666/04 20130101;
C09D 133/066 20130101 |
Class at
Publication: |
525/450 |
International
Class: |
C09D 167/04 20060101
C09D167/04 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 25, 2005 |
JP |
2005-339838 |
Claims
1. A paint composition comprising: a hydroxyl group containing
resin (A), comprising structural units based on
2,2-dimethylolalkanoic acid, a hydroxyl group value of from 200 to
400 mgKOH/g and less than 25 weight % in the resin solid fraction
of structural units based on a lactone compound; a hydroxyl group
containing resin (B), comprising a hydroxyl group value from 50 to
200 mgKOH/g, and from 25 to 75 weight % in the resin solid fraction
of structural units based on a lactone compound; and a crosslinking
agent (C) comprising at least two OH-reactive functional groups per
molecule; wherein the resin solid fraction weight ratio (A)/(B) of
the hydroxyl group containing resin (A) and the hydroxyl group
containing resin (B) is from 90/10 to 10/90.
2. The paint composition of claim 1, wherein at least 40% of the
hydroxyl groups of the hydroxyl group containing resin (A) are
hydroxyl groups of a 2,2-dimethylolalkanoic acids and the hydroxyl
groups produced by the addition reaction with an epoxy group
containing radically polymerizable monomer or polymer of a hydroxyl
group of a 2,2-dimethylolalkanoic acid, or a combination
thereof.
3. The paint composition of claim 1, wherein the
2,2-dimethylolalkanoic acid is 2,2-dimethylolbutanoic acid or
2,2-dimethylolpropionic acid.
4. The paint composition of claim 1, wherein the hydroxyl group
containing resin (A) and the hydroxyl group containing resin (B)
are acrylic resins of weight average molecular weight from 1,000 to
30,000.
5. The paint composition of claim 1, wherein the crosslinking agent
(C) is an isocyanate compounds, a melamine resin, or a combination
thereof.
6. A method of paint finishing comprising applying the paint
composition claim 1.
7. A painted object comprising the paint composition of claim 1.
Description
TECHNICAL FIELD
[0001] The invention concerns novel paint compositions, a method of
paint finishing and the resulting painted objects. More precisely,
the invention concerns paint compositions and a method of paint
finishing with which paint films which have excellent car-wash
scratching resistance, acid resistance, staining resistance, water
resistance, weather resistance and appearance can be obtained in
the automobile painting field, and the resulting painted
objects.
BACKGROUND TECHNOLOGY
[0002] In recent years problems have arisen with the formation of
scratches on automobile paint films as a result of car-wash
machines and there is a pressing need for the development of paints
which have excellent car-wash scratching resistance and durability.
In the past softening the paint film itself by reducing the Tg and
crosslink density of the paint film and improving the scratching
resistance has been considered as a means of resolution which
improves the scratching resistance but, although the car-wash
scratching resistance is improved, this results in the other
features such as hardness, staining resistance, acid resistance and
the like which are required of the paint film obtained being
lost.
[0003] Paint compositions which contain as essential components (A)
acrylic copolymers of acid value from 25 to 125 and hydroxyl group
value from 30 to 150 which contain (meth)acrylic acid derivative
units, (B) acrylic copolymer of epoxy equivalent from 230 to 1500
and hydroxyl group value from 30 to 150 which contain unsaturated
monomer units which have epoxy groups, where the (A) and (B)
components are copolymers which may contain unsaturated monomers
which are .epsilon.-caprolactone modifications of acrylic monomers
which have hydroxyl groups, and (C) amino resins are known as a
method of obtaining paint films which have excellent acid
resistance and scratching resistance (for example, see Patent
Citation 1). However, with these paint compositions there is a
weakness in that the acid rain resistance is reduced since they
have an amino resin as an essential component.
[0004] Furthermore, similarly high solid fraction paint
compositions which are characterized by the fact that they contain
in the proportions indicated (A) from 5 to 30 wt % of hydroxyl
group containing lactone modified oligomer of weight average
molecular weight not more than 1,000 and of which the hydroxyl
group value is from 200 to 800, (B) from 5 to 50 wt % of hydroxyl
group containing resin of weight average molecular weight from
1,000 to 6,000 and of which the hydroxyl group value is from 50 to
200, (C) from 30 to 70 wt % of polyisocyanate compound and (D) from
3 to 30 wt % of melamine resin are known as paint compositions in
which two types of hydroxyl group containing resin are used and
which have excellent finished appearance, paint film hardness, acid
rain resistance and scratching resistance, and which have a high
solid fraction (for example, see Patent Citation 2). However, with
these paint compositions the glass transition point (Tg) of the
paint film is inevitably reduced by the use of the low molecular
weight hydroxyl group containing lactone oligomer and there is a
weakness in that the staining resistance and the weather resistance
are reduced.
[0005] Furthermore, paint compositions which have as essential
components (a) from 30 to 90 parts by mass of a lactone modified
acrylic polyol resin which has been obtained by the ring-opening
addition reaction in the absence of a catalyst on adding from 10 to
200 parts by mass of lactone compound to 100 parts by mass of an
acrylic polyol resin of which the hydroxyl group value is from 75
to 250 mgKOH/g and the acid value is from 0.5 to 50 mgKOH/g, (b)
from 10 to 70 parts by mass of polyisocyanate compound and (c) from
0.01 to 20 parts by mass of a specified alkoxysilane partially
hydrolyzed condensate are known as paint compositions where the
staining resistance and impact resistance are excellent and where
at the same time the appearance, weather resistance, water
resistance and the like are also excellent (for example, see Patent
Citation 3). However, with these paint compositions there is a
weakness in that the balance of the paint film performance in terms
of the car-wash scratching resistance and the acid rain resistance,
staining resistance and weather resistance cannot be maintained
satisfactorily because of the presence of one type of lactone
modifier acrylic polyol resin.
[Patent Citation 1]
[0006] Japanese Unexamined Patent Application Laid Open
H5-171103
[Patent Citation 2]
[0006] [0007] Japanese Unexamined Patent Application Laid Open
2002-105397
[Patent Citation 3]
[0007] [0008] Japanese Unexamined Patent Application Laid Open
2003-313493
DISCLOSURE OF THE INVENTION
[Problems to be Resolved by the Invention]
[0009] The invention is intended to provide paint compositions with
which paint films which have excellent car-wash scratching
resistance, acid resistance, staining resistance, water resistance,
weather resistance and appearance can be obtained, a method of
paint finishing in which these paint compositions are used, and the
painted objects.
[Means of Resolving These Problems]
[0010] As a result of thorough research carried out with a view to
resolving the abovementioned problems, the inventors have
discovered that these aims can be achieved by means of a paint
composition in which resins which have different hydroxyl group
values are combined, and which has as essential components two
types of hydroxyl group containing resin in which the amounts of
lactone compound modification are different and a crosslinking
agent which reacts with hydroxyl groups, and the invention is based
upon these findings.
[0011] That is to say, the invention provides a paint composition
which has as essential components a hydroxyl group containing resin
(A) of hydroxyl group value including the hydroxyl groups
originating from a 2,2-methylolalcanoic acid from 200 to 400
mgKOH/g and which contains less than 25 mass % in the resin solid
fraction of structural units based on a lactone compound, a
hydroxyl group containing resin (B) of hydroxyl group value from 50
to 200 mgKOH/g which contains from 25 to 75 mass % in the resin
solid fraction of structural units based on a lactone compound, and
a crosslinking agent (C) which includes in one molecule at least
two functional groups which react with hydroxyl groups, and in
which the proportions of the hydroxyl group containing resin (A)
and the hydroxyl group containing resin (B) are, as the resin solid
fraction mass ratio (A)/(B), from 90/10 to 10/90.
[0012] Furthermore, the invention provides a composition in which,
in the abovementioned paint composition, at least 40% of the
hydroxyl groups of the hydroxyl group containing resin (A) are the
hydroxyl groups of a 2,2-dimethylolalkanoic acid and the hydroxyl
groups produced by the addition reaction to an epoxy group
containing radically polymerizable monomer or polymer of a hydroxyl
group of 2,2-dimethyloilalkanoic acid.
[0013] Furthermore, the invention provides a paint composition in
which, in the abovementioned paint composition, the
2,2-dimethylolalkanoic acid is 2,2-dimethylolbutanoic acid or
2,2-dimethylolpropionic acid.
[0014] Furthermore, the invention provides a paint composition in
which, in the abovementioned paint composition, the hydroxyl group
containing resin (A) and the hydroxyl group containing resin (B)
are acrylic resins of weight average molecular weight from 1,000 to
30,000.
[0015] Furthermore, the invention provides a paint composition in
which, in the abovementioned paint composition, the crosslinking
agent (C) is an isocyanate compound and/or a melamine resin.
[0016] Furthermore, the invention provides a method of paint
finishing in which the abovementioned paint composition is applied
as a top-coat paint and, furthermore, the invention provides the
painted objects which have been painted with the abovementioned
paint finishing method.
[Effect of the Invention]
[0017] The invention provides paint films which have excellent acid
resistance, staining resistance, water resistance and weather
resistance and which have in particular excellent car-wash
scratching resistance. Furthermore, the method of paint finishing
in which paint compositions of this invention are used provides
paint films which have an excellent appearance, and the painted
objects are excellent in terms of the aforementioned paint film
performance.
EMBODIMENT OF THE INVENTION
[0018] Two types of hydroxyl group containing resin, (A) and (B),
are used in a paint composition of this invention.
[0019] The hydroxyl group containing resin (A) is a resin of which
the hydroxyl group value including the hydroxyl groups originating
from a 2,2-dimethylolalkanoic acid of from 200 to 400 mgKOH/g and
which contains less than 25 mass % in the resin solid fraction of
structural units based on a lactone compound. Hydroxyl group
containing acryl resins and polyester resins can be cited for the
hydroxyl group containing resin (A), but the use of an acrylic
resin is preferred.
[0020] In this invention the hydroxyl group containing resin (A)
provides staining resistance and paint film hardness by providing a
paint film which has an adequate crosslink density.
[0021] The hydroxyl group value of the hydroxyl group containing
resin (A) is from 200 to 400 mgKOH/g, but it is preferably from 200
to 320 mgKOH/g and most desirably from 200 to 280 mgKOH/g. In those
cases where the hydroxyl group value is less than 200 mgKOH/g the
staining resistance is reduced and paint film hardness is not
obtained because the crosslink density of the paint film is
inadequate. Furthermore, in those cases where the hydroxyl group
value exceeds 400 mgKOH/g the appearance of the paint film is poor
because compatibility with the crosslinking agent is not
obtained.
[0022] Furthermore, the hydroxyl group containing resin (A) is a
resin which contains less than 25 mass % in the resin solid
fraction of structural units based on a lactone compound, but the
content is preferably at least 2 mass % and less than 25 mass % and
most desirably at least 5 mass % and less than 25 mass %. If the
structural unit based on a lactone compound content of the hydroxyl
group containing resin (A) is 25 mass % or more then the hardness
and staining resistance of the paint film obtained are reduced.
[0023] The hydroxyl group containing resin (B) is a resin which has
a hydroxyl group value from 50 to 200 mgKOH/g and which contains
from 25 to 75 mass % in the resin solid fraction of structural
units based on a lactone compound. The hydroxyl group containing
resins (B) include hydroxyl group containing resins such as acrylic
resins and polyester resins, but the use of acrylic resins is
preferred.
[0024] In this invention the hydroxyl group containing resin (B)
can improve the car-wash scratching resistance by providing the
paint film with elasticity.
[0025] The hydroxyl group value of the hydroxyl group containing
resin (B) is from 50 to 200 mgKOH/g, but it is preferably from 80
to 190 mgKOH/g, and most desirably from 100 to 180 mgKOH/g. In
those cases where the hydroxyl group value is less than 50 mgKOH/g
paint film hardness is not obtained and the staining resistance is
reduced, and in those cases where the hydroxyl group value exceeds
200 mgKOH/g failure of the paint film appearance occurs because
compatibility with the crosslinking agent is not obtained.
[0026] The hydroxyl group containing resin (B) is a resin which
contains from 25 to 75 mass % in the resin solid fraction of
structural units which are based on a lactone compound, but the
content is preferably from 25 to 60 mass % and most desirably from
25 to 50 mass %. In those cases where the structural units based on
a lactone compound included in the hydroxyl group containing resin
(B) account for less than 25 mass % then the car-wash scratching
resistance of the paint film obtained is reduced, and if the
content exceeds 75 mass % then the compatibility of the paint is
reduced and the hardness and staining resistance of the paint film
are poor.
[0027] Furthermore, the weight average molecular weights of the
hydroxyl group containing resins (A) and (B) are preferably from
1,000 to 30,000, more desirably from 2,000 to 20,000, and most
desirably from 3,000 to 15,000. In those cases where the weight
average molecular weights are less than 1,000 there is a tendency
for paint film hardness not to be obtained and appearance failure
when wet-on-wet painting tends to occur, and in those cases where
the weight average molecular weights exceeds 30,000 appearance
failure of the paint film tends to occur as a result of a reduction
of the compatibility with the crosslinking agent.
[0028] Examples of the lactone compounds which can be used in the
invention include .beta.-methyl-.delta.-valerolactone,
.gamma.-valerolactone, .delta.-valerolactone, .delta.-caprolactone,
.gamma.-caprolactone, .epsilon.-caprolactone, .beta.-propiolactone,
.gamma.-butyrolactone, .gamma.-nonanoic lactone and
.delta.-dodecalactone, but .epsilon.-caprolactone is especially
desirable. One of these lactone compounds may be used, or a
combination of two or more types may be used.
[0029] The abovementioned lactone compounds may be incorporated
into the resin by means of a ring-opening addition reaction with
the hydroxyl groups of the hydroxyl group containing resin (A)
and/or the hydroxyl group containing resin (B), or they may be
incorporated into the hydroxyl group containing resin (A) and/or
hydroxyl group containing resin (B) by forming a lactone modified
hydroxyl group containing radically polymerizable monomer by means
of a ring-opening addition reaction with the hydroxyl group of a
hydroxyl group containing radically polymerizable monomer
beforehand and copolymerizing this lactone modified hydroxyl group
containing radically polymerizable monomer.
[0030] Furthermore, at least 40%, and more desirably at least 50%,
of the hydroxyl groups included in the hydroxyl group containing
resin (A) of this invention are preferably hydroxyl groups of (a) a
2,2-dimethylolalcanoic acid and hydroxyl groups produced by an
addition reaction on (b) an epoxy group containing radically
polymerizable monomer or polymer of a 2,2-dimethylolalkanoic
acid.
[0031] In those cases where the hydroxyl groups originating from
the abovementioned (a) component and the hydroxyl groups
originating from the abovementioned (b) component account for less
than 40% of the hydroxyl groups included in the hydroxyl group
containing resin (A) there is a tendency for the appearance to
decline due to compatibility failure of the paint.
[0032] Furthermore, 2,2-dimethylolalkanoic acids which include a
carboxyl group which has from five to ten carbon atoms, preferably
from five to eight carbon atoms, and most desirably five or six
carbon atoms, are preferred for the (a) component. Actual examples
of the (a) component include 2,2-dimethylolpropionic acid,
2,2-dimethylolbutanoic acid, 2,2-dimethylolpentanoic acid and
2,2-dimethylolhexanoic acid, but 2,2-dimethylolpopionic acid and
2,2-dimethylolbutanoic acid are preferred because they provide
resins which have a lower polarity.
[0033] As indicated above, hydroxyl groups can be provided in a
resin by subjecting the (a) component 2,2-dimethylolalkanoic acid
to an addition reaction with a (b) component radically
polymerizable monomer or polymer which has epoxy groups, and the
addition reaction of the (a) component 2,2-dimethylolalkanoic acid
and the (b) component epoxy groups may be carried out before the
copolymerization of the (b) component monomer and other radically
polymerizable monomer, during the copolymerization or after the
copolymerization has been completed.
[0034] The amount of the (a) component 2,2-dimethylolalkanoic acid
compounded depends on the amount of the (b) component and the
hydroxyl group value of the resin, but the (a) component acid is
preferably used in an amount within the range of not more than 1.2
times the amount of (b) component epoxy groups as a mol ratio. In
those case where there the (a) component acid is in excess of 1.2
times the amount of epoxy groups as a mol ratio the unreacted acid
sometimes precipitates out in the resin and this is undesirable. No
particular limitation is imposed as a lower limit for the amount of
the (a) component 2,2-dimethylolalkanoic acid compounded, but the
presence of at least 5 mass % in the resin solid fraction is
preferred. In those cases where the carboxyl groups of the (a)
component 2,2-dimethylolalkanoic acid is in excess of the (b)
component epoxy groups the excess carboxyl groups of the (a)
component 2,2-dimethylolalkanoic acid cannot react with (b)
component epoxy groups and so the (a) component
2,2-dimethylolalkanoic acid which does not have a polymerizable
double bond may be present in an unreacted form in a hydroxyl group
containing resin composition for paint purposes of this invention.
On the other hand, in those cases where the (b) component epoxy
groups are in excess of the carboxyl groups of the (a) component
2,2-dimethylolalkanoic acid the hydroxyl group containing resin
obtained may have epoxy groups.
[0035] Furthermore, the epoxy group containing radically
polymerizable monomer which is one type of (b) component which can
be used for obtaining a hydroxyl group containing resin composition
for paint purposes of this invention is an epoxy group containing
radically polymerizable monomer which has one or more radically
polymerizable carbon-carbon double bond, and the number of
radically polymerizable carbon-carbon double bonds is preferably
not more than two and most desirably one. The (b) component may
have functional groups other than the epoxy group but those which
do not react with the hydroxyl groups and carboxyl groups of the
(a) component are preferred, and those which have no functional
group other than the epoxy group are most desirable. Actual
examples of the (b) component include glycidyl acrylate, glycidyl
methacrylate, 3,4-epoxycyclohexylmethyl acrylate and
3,4-epoxycyclohexylmethyl methacrylate, and one type, or a
combination of two or more types, can be used.
[0036] The epoxy group containing polymers which are the other type
of (b) component are polymers obtained by polymerizing the
abovementioned epoxy group containing radically polymerizable
monomers.
[0037] Moreover, as with the hydroxyl group containing resin (A), a
combination of 2,2-dimethylolalkanoic acid and epoxy group
containing radically polymerizable monomer or polymer can also be
used in the hydroxyl group containing resin (B).
[0038] Furthermore, with the hydroxyl group containing resin (A)
and the hydroxyl group containing resin (B) hydroxyl groups due to
radically polymerizable monomers which have hydroxyl groups can
also be used for the hydroxyl groups other than the hydroxyl groups
of 2,2-dimethylolalkanoic acid and the hydroxyl groups produced by
an addition reaction on epoxy group containing radically
polymerizable monomer or polymer of 2,2-dimethylolalkanoic
acid.
[0039] Examples of these radically polymerizable monomers which
have hydroxyl groups include 2-hydroxyethyl (meth)acrylate,
2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl(meth)acrylate,
4-hydroxybutyl (meth)-acrylate, allyl alcohol; versatic acid
glycidyl ester adducts of (meth)acrylic acid;
.epsilon.-caprolactone adducts of 2-hydroxyethyl (meth)acrylate,
2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl(meth)acrylate and
4-hydroxybutyl (meth)acrylate; and ethylene oxide and/or propylene
oxide adducts of 2-hydroxyethyl (meth)-acrylate, 2-hydroxypropyl
(meth)acrylate, 3-hydroxy-propyl(meth)acrylate and 4-hydroxybutyl
(meth)acrylate.
[0040] Other radically polymerizable monomers can be used and
copolymerized in the hydroxyl group containing resin (A) and the
hydroxyl group containing resin (B) and actual examples of these
radically polymerizable monomers include methyl acrylate, ethyl
acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate,
isobutyl acrylate, sec-butyl acrylate, hexyl acrylate, cyclohexyl
acrylate, 2-ethylhexyl acrylate, octyl acrylate, lauryl acrylate,
stearyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl
methacrylate, isopropyl methacrylate, n-butyl methacrylate,
isobutyl methacrylate, sec-butyl methacrylate, hexyl methacrylate,
cyclohexyl methacrylate, 2-ethylhexyl methacrylate, octyl
methacrylate, lauryl methacrylate, stearyl methacrylate, styrene,
acrylonitrile, methacrylonitrile, acrylamide and methacrylamide,
and one type, or a combination of two or more types, can be
used.
[0041] A radical polymerization initiator may be compounded when
carrying out the radical polymerization. Examples of the radical
polymerization initiators include azo compounds such as
2,2'-azobis-isobutyronitrile,
2,2'-azobis-2,4-dimethylvaleronitrile, 4,4'-azobis-4-cyanovaleric
acid, 1-azobis-1-cyclohexanecarbonitrile and
dimethyl-2,2'-azobisisobutyrate; and organic peroxides such as
methyl ethyl ketone peroxide, cyclohexanone peroxide,
3,5,5-trimethylhexanone peroxide,
1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane,
1,1-bis(t-butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)octane,
t-butyl hydroperoxide, diisopropylbenzene hydroperoxide, dicumyl
peroxide, t-butylcumyl peroxide, isobutyl peroxide, lauroyl
peroxide, benzoyl peroxide, diisopropyl peroxydicarbonate,
t-butylperoxy 2-ethylhexanoate, t-butylperoxy neodecanate,
t-butylperoxy laurate, t-butylperoxy benzoate and t-butylperoxy
isopropyl carbonate. One of these radical polymerization initiators
may be used alone, or a combination of two or more types may be
used.
[0042] No particular limitation is imposed upon the amount of
radical polymerization initiator compounded, but an amount of from
0.01 to 20 mass % with respect to the total amount of radically
polymerizable monomer is preferred.
[0043] Reducing agents such as dimethylaniline, ferrous salts such
as ferrous sulfate, ferrous chloride and ferrous acetate, acidic
sodium sulfite, sodium thiosulfate and rongalite may be combined,
as required, with these radical polymerization initiator systems,
but care is require with the selection so that the polymerization
temperature is not too low.
[0044] Moreover, one type, or a combination of a plurality of
types, of known reaction catalysts such as Lewis acids, tertiary
amines, ammonium salts, phosphonium salts and the like can be used,
as required, with a view to promoting the reaction between the
carboxyl groups of the (a) component and the epoxy groups of the
(b) component.
[0045] The organic solvents which can be used in the production of
the hydroxyl group containing resins (A) and the hydroxyl group
containing resins (B) of this invention are preferably solvents
which do not have functional groups which react with the carboxyl
groups of the (a) component, the epoxy groups of the (b) component
or lactone compounds.
[0046] Examples of suitable organic solvents which can be used in
the production of the hydroxyl group containing resins (A) and the
hydroxyl group containing resins (B) of this invention include
alicyclic hydrocarbon solvents such as cyclohexane and
ethylcyclohexane, aromatic hydrocarbon solvents such as toluene,
xylene, ethylbenzene and aromatic naphtha, ketone solvents such as
acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone
and isophorone, ester-based solvents such as ethyl acetate, n-butyl
acetate, isobutyl acetate, 3-methoxybutyl acetate and
bis(2-ethylhexyl)adipate, ether based solvent such as dibutyl
ether, tetrahydrofuran, 1,4-dioxane and 1,3,5-trioxane, and
nitrogen-containing solvents such as acetonitrile, valeronitrile,
N,N-dimethylformamide and N,N-diethylformamide. The organic solvent
may be of one type alone or it may be a mixed solvent comprising a
plurality of two or more types. At this time the solid fraction
concentration of the hydroxyl group containing resin can be
selected optionally within the range where the dispersion stability
of the resin is not lost, but generally the solid fraction
concentration is from 10 to 70 mass %.
[0047] The method of adding the organic solvent and radical
polymerization initiator is optional when producing the hydroxyl
group containing resins (A) and hydroxyl group containing resins
(B) of this invention, but methods in which the radically
polymerizable monomer which includes the (b) component is added
dropwise from a drip feed vessel while stirring the (a) component
or an organic solvent solution thereof which has been introduced
into a reaction vessel, or a method in which the (a) component or
an organic solvent solution thereof and the radically polymerizable
monomer which includes the (b) component, or an organic solvent
solution thereof, are both added dropwise from drip feed vessels
are preferred with a view to controlling the heat of polymerization
and the heat of reaction. Moreover, the radically polymerizable
monomer which includes the (b) component may be just the (b)
component radically polymerizable monomer which has epoxy groups or
it may be a combination of the (b) component radically
polymerizable monomer which has epoxy groups and other radically
polymerizable monomer.
[0048] The polymerization temperature of the abovementioned
reactions differs according to the type of radical polymerization
initiator and whether or not a reducing agent is used conjointly
and whether or not a reaction catalyst for the carboxyl groups and
epoxy groups is present, but the polymerizations are preferably
carried out under conditions of from 50 to 200.degree. C., and more
desirably under conditions of from 80 to 160.degree. C. In those
cases where the polymerization temperature is below 50.degree. C.
the reaction of the (a) component carboxyl groups and (b) component
epoxy groups does not proceed satisfactorily and phase separation
of the radically polymerizable monomer and the hydroxyl group
containing resin is liable to occur. On the other hand, in those
cases where it exceeds 200.degree. C. side reactions such as
unexpected depolymerization occur.
[0049] The mixing proportions as the mass ratio of the resin solid
fractions used of the hydroxyl group containing resin (A) and the
hydroxyl group containing resin (B) in a paint composition in this
invention are preferably within the range from 90/10 to 10/90, and
most desirably within the range from 80/20 to 40/60. With less than
10 mass % with respect to the total amount of hydroxyl group
containing resin (A) and hydroxyl group containing resin (B) of the
hydroxyl group containing resin (B) the car-wash scratching
resistance of the paint film obtained is reduced, and in those
cases where it exceeds 90 mass % the staining resistance and acid
rain resistance are reduced.
[0050] The crosslinking agents (C) which can be used in the paint
compositions of this invention are crosslinking agents which have
in one molecule at least two, and preferably at least three,
functional groups which react with hydroxyl groups, and examples
include isocyanate compounds which have in one molecule at least
two, and preferably three or more, functional groups such as
isocyanate groups or blocked isocyanate groups, and melamine
resins. One type of crosslinking agent may be used alone, or a
combination of two or more types may be used.
[0051] Examples of polyisocyanate compounds which have two or more
isocyanate groups in one molecule include p-phenylene diisocyanate,
biphenyl diisocyanate, tolylene diisocyanate,
3,3'-dimethyl-4,4'-biphenylene diisocyanate, 1,4-tetramethylene
diisocyanate, hexamethylene diisocyanate,
2,2,4-trimethylhexane-1,6-diisocyanate,
methylenebis(phenylisocyanate), lysine methyl ester diisocyanate,
bis(isocyanatoethyl) fumarate, isophorone diisocyanate,
methylcyclohexyl diisocyanate,
2-isocyanatoethyl-2,6-diisocyanatohexanoate and the biuret and
isocyanurate forms of these.
[0052] The isocyanate compounds where a polyisocyanate compound
which has two or more isocyanate groups in one molecule, for
example a polyisocyanate such as hexamethylene diisocyanate,
phenylene diisocyanate, xylylene diisocyanate or isophorone
diisocyanate, has been blocked with a blocking agent such as an
active methylene system, for example methyl acetoacetate or
dimethyl malonate, or an oxime can be cited as isocyanate compounds
which have blocked isocyanate groups.
[0053] The alkyl etherified melamine resins are preferred for the
melamine resins, and these include the methylolated amino resins
obtained by reacting melamine and aldehydes. Examples of the
aldehydes include formaldehyde, paraformaldehyde, acetaldehyde and
benzaldehyde. Furthermore, those where a methyolated amino resin
has been etherified with one type, or two or more types, of lower
alcohol can also be used, and the monohydric alcohols such as
methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol,
n-butyl alcohol, isobutyl alcohol 2-ethylbutanol and
2-ethyl-hexanol can be cited as examples of the alcohols which can
be used for the etherification. From among these the methylolated
melamine resins and the melamine resins where at least some of the
methylol groups of a methylolated melamine resin have been
etherified with a primary alcohol which has from 1 to 4 carbon
atoms are ideal.
[0054] Commercial examples of the abovementioned melamine resins
include butyl etherified melamine resins such as Yuban 20SE-60 and
Yuban 225 (trade names, both produced by the Mitsui Kagaku Co.) and
Superbekkamine G840 and Superbekkamine G821 (trade names, both
produced by the Dainippon Ink Kagaku Co.), and methyl etherified
melamine resins such as Sumimar M-100, Sumimar M-40S and Sumimar
M-55 (trade names, all produced by the Sumitomo Kagaku Co.) and
Saimel 303, Saimel 325, Saimel 350 and Saimel 370 (trade names, all
produced by the Nippon Scitech Industries Co.).
[0055] In those cases where isocyanate compounds and melamine
resins are used conjointly as crosslinking agents they are
preferably used in a solid fraction mass ratio of from 100/0 to
75/25, and most desirably of from 100/0 to 85/15. In those cases
where the mixing proportion of melamine resin exceeds 25 mass % the
car-wash scratching resistance and acid resistance of the paint
film obtained are reduced.
[0056] The mixing ratio of the hydroxyl group containing resin (A)
and the hydroxyl group containing resin (B) with the crosslinking
agent (C) is preferably such that, as a resin solid fraction mass
ratio, when the total of (A) and (B) is 100, from 10 to 190, and
more desirably from 15 to 120, of (C) are used. In those cases
where the proportion by mass of crosslinking agent is less than 10
per 100 of hydroxyl group containing resin the staining resistance
is reduced and a paint film with adequate hardness is not obtained.
Furthermore, in those cases where the proportion exceeds 190 the
paint film becomes brittle and a reduction in weather resistance
occurs.
[0057] The paint compositions of this invention can be used as they
are or with the addition, as required, of organic solvents and
various additives, such as ultraviolet absorbers,
photo-stabilizers, antioxidants, surfactants, surface controlling
agents, hardening reaction catalysts, anti-static agents, perfumes,
water removing agents and rheology-controlling agents such as
polyethylene wax, polyamide wax and fine internally crosslinked
resin particles for example.
[0058] The paint compositions of this invention may be used as
clear paints, or coloring agents such as dyes, pigments and the
like may compounded and they may be used as colored paints.
[0059] The paint compositions of this invention are preferably used
as top-coat paint compositions.
[0060] The paint finishing method for a top-coat paint composition
of this invention is, for example, a two-coat one-bake paint
finishing method in which a colored base-coat is painted on the
base material and the paint composition of this invention is
painted on as a top coat without crosslinking or an over-coat paint
finishing method where a colored base-coat is painted on the base
material and a top-coat paint is painted on without crosslinking
and, after baking both at the same time, a paint composition of
this invention is painted on as an over-coat paint and baked, and
there are also methods where in the aforementioned over-coating
method a primer paint is painted on to ensure adhesion with the
underlying coat and the paint composition of this invention is
painted on as an over-coat clear paint without crosslinking.
[0061] The aforementioned colored base coat paint, top-coat paint,
over-coating paint or primer paint is adjusted to the prescribed
viscosity by heating or adding an organic solvent or reactive
diluent, as required, and the painting is carried out using a
painting machine of the type generally used such as an air sprayer,
electrostatic air sprayer, roll coater, flow coater or a painting
machines with dipping system for example, or using a brush or a bar
coater or an applicator, for example. From among these methods
spray painting is preferred.
[0062] The amount of a paint composition of this invention which is
applied is preferably such that the dry film thickness is generally
from 10 to 100 .mu.m. In general a paint film which is obtained by
painting with a paint composition of this invention is preferably
baked.
[0063] Furthermore, the baking temperature should generally be
selected appropriately within the range from 120 to 180.degree. C.
Moreover, the baking time should generally be selected
appropriately within the range from 10 to 60 minutes.
[0064] Furthermore, examples of the base material on which a paint
composition of this invention is painted include organic materials
and inorganic materials such as wood, glass, metal, cloth,
plastics, foams, elastomers, paper, ceramics, concrete and
plasterboard. These base materials may be materials which have been
surface treated beforehand or they may be materials on which a
paint film has been formed on the surface beforehand.
[0065] Actual examples have been indicated so far, but the method
of paint finishing with a paint composition of this invention is
not limited to just these methods.
[0066] Examples of painted objects which can be obtained with a
clear composition of this invention include structures, wooden
products, metal products, plastic products, rubber products,
processed paper, ceramic products and glass products. In more
practical terms these include automobiles, automobile parts (for
example bodies, bumpers, spoilers, mirrors, wheels, internal
decorative parts and those made of various materials), metal sheets
such as steel sheet, bicycles, bicycle parts, street furnishings
(for example, guard rails, traffic signs and sound-deadening
walls), tunnel furnishings (for example side-wall sheets), ships,
railway rolling stock, aircraft, furniture, musical instruments,
domestic electrical goods, building materials, containers, office
equipment, sports goods, toys and the like.
ILLUSTRATIVE EXAMPLES
[0067] The invention is described in more practical terms below by
means of illustrative examples, but the invention is in no way
limited by these illustrative examples. Moreover, the performance
of the paint films obtained with the clear paint compositions of
this invention was determined in each case in the ways indicated
below.
(1) Appearance
[0068] The appearance was evaluated by visual observation of the
paint film in accordance with the following criteria. [0069] O:
When a fluorescent lamp was reflected in the paint film the
fluorescent lamp was reflected distinctly. [0070] .DELTA.: When a
fluorescent lamp was reflected in the paint film the outline
(profile) of the fluorescent lamp was slightly blurred. [0071] X:
When a fluorescent lamp was reflected in the paint film the outline
(profile) of the fluorescent lamp was markedly blurred.
(2) Hardness
[0072] This was evaluated by touching with a finger on the basis of
the following criteria. [0073] O: The paint film did not feel tacky
[0074] .DELTA.: The paint film felt slightly tacky [0075] X: The
paint film felt distinctly tacky
(3) Car-Wash Scratching Resistance
[0076] Dirty water (JIS Z-8901-84, a 10/99/1 mixture of type 8
dust/water/neutral detergent) was applied with a brush to a test
sheet on the surface of which a paint film had been formed and then
it was cleaned with a car-wash brush rotating at 150 rpm for 10
seconds in an automatic car-wash machine and the test sheet was
rinsed with flowing water. This procedure was repeated ten times
and then the extent of scratching of the test sheet surface was
determined by measuring the L* value with a color difference meter
(CR-331, produced by the Minolta Camera Co.). A low numerical value
is good.
(4) Acid Resistance
[0077] A 40% sulfuric acid aqueous solution (0.2 ml) was placed as
a spot on the test sheet and then heated to 60.degree. C. for 15
minutes and then rinsed with water and then the extent to which a
mark had been produced was assessed visually. [0078] O: Virtually
no change to be seen in the paint film [0079] .DELTA.: A slight
water mark was seen [0080] X: A pronounced water mark was seen
(5) Staining Resistance
[0081] Dirty water (JIS Z-8901-84, a 1.3/98/0.5/0.2 by mass mixture
of type 8 dust/water/carbon black/yellow ochre) was coated onto a
test sheet on the surface of which a paint film had been formed and
then dried for 10 minutes at 50.degree. C. and, after carrying out
eight cycles, the paint film was cleaned with a fixed force with a
polishing cloth while rinsing with water and the staining mark was
assessed visually and evaluated in accordance with the following
criteria. [0082] 0: No staining [0083] .DELTA.: Staining material
remained in parts [0084] X: Staining material remained all over
(6) Water Resistance
[0085] After a test sheet on the surface of which a paint film had
been formed had been exposed outdoors for 3 months in accordance
with JIS K-5500 (1990) 9.9 Weather Resistance, the color of the
unwashed surface of the paint film was measured on the basis of the
JIS K-5400 (1990) 7.4.2 Color Meter Measuring Method for Paint
Films, the .DELTA.L* value was calculated by subtracting the L*
value before the test from the L* value after immersion in warm
water at 40.degree. C. for 240 hours and the whitening of the paint
film was assessed. A small numerical value is good.
(7) Weather Resistance
[0086] The state of the paint film was assessed visually after
exposing a test sheet on the surface of which a paint film had been
formed for 3000 hours using a sunshine carbon arc lamp type
accelerated weather resistance testing machine (JIS K-5400 (1990)
9.8.1).
Examples of Production 1 to 6
Production of Hydroxyl Group Containing Solutions for Paint
Purposes A-1 to A-6
[0087] The xylene and 2,2-dimethylolbutanoic acid of the
composition shown in Table 1 was introduced into a four-necked
flask which had been furnished with a thermometer, a reflux
condenser, a stirrer and a dropping funnel and heated while being
stirred under a current of nitrogen and maintained at 140.degree.
C. Next, the mixture of monomer and polymerization initiator of the
composition shown in Table 1 (the drip-feed component) was drip fed
from the dropping funnel at a uniform rate over a period of 2 hours
at a temperature of 140.degree. C. After the drip-feed had been
completed the temperature of 140.degree. C. was maintained for 1
hour and then the reaction temperature was lowered to 110.degree.
C. Subsequently, a polymerization initiator solution of the
composition shown in Table 1 (the supplementary catalyst) was added
and, after maintaining a temperature of 110.degree. C. for 2 hours,
the amount of .epsilon.-caprolactam indicated in Table 1 was
introduced and the reaction was completed on maintaining a
temperature of 150.degree. C. for 3 hours and the hydroxyl group
containing resin solution for paint purposes A-1 was obtained.
Furthermore, the hydroxyl group containing resin solutions for
paint purposes A-2 to A-6 were obtained in the same way as the
hydroxyl group containing resin for paint purposes A-1 except that
the amounts of the raw materials introduced shown in Table 1 were
changed.
TABLE-US-00001 TABLE 1 Example of Example of Example of Example of
Example of Example of Production 1 Production 2 Production 3
Production 4 Production 5 Production 6 Hydroxyl group containing
resin for paint A-1 A-2 A-3 A-4 A-5 A-6 purposes Initial Xylene
32.9 32.9 32.9 32.9 32.9 32.9 Introduction 2-2-Dimethylolbutanoic
6.6 7.8 9.2 3.6 4.8 12.5 acid (DMBA) Drip-feed 2-Ethylhexyl
methacrylate 17.3 5.1 17.0 34.8 0.5 12.6 Component (EHMA)
2-Hydroxyethyl acrylate 40.8 (HEA) 2-Hydroxyethyl 17.4 26.7 11.5
11.4 1.9 methacrylate ((HEMA) Glycidyl methacrylate 7.9 8.4 7.9 4.2
4.9 13.2 t-Butylperoxy-2- 5.0 5.0 5.0 5.0 5.0 5.0 ethylhexanoate
Catalyst Component t-Butylperoxy-2- 0.1 0.1 0.1 0.1 0.1 0.1
ethylhexanoate Xylene 1.0 1.0 1.0 1.0 1.0 1.0 Supplementary
.epsilon.-Caprolactam 10.8 12.0 14.4 6.0 9.0 19.8 Component Xylene
1.0 1.0 1.0 1.0 1.0 1.0 Total 100.0 100.0 100.0 100.0 100.0 100.0
Resin hydroxyl group value (mgKOH/g) 250 340 260 150 420 250
Involatile fraction (%) 65.1 65.1 65.1 65.1 65.1 65.1 Weight
average molecular weight 5000 5000 5000 5000 5000 5000 Amount of
lactone compound in the resin solid 16.6 18.4 24.0 10.0 15.0 33.0
fraction (mass %) Proportion of hydroxyl groups originating from
50.0 43.5 66.8 45.3 21.7 94.4 dimethylolalkanoic acid among the
hydroxyl groups (mass %)
Examples of Production 7 to 13
Production of Hydroxyl Group Containing Solutions for Paint
Purposes B-1 to B-7
[0088] The hydroxyl group containing resin solutions B-1 to B-7
where obtained in the same way as the hydroxyl group containing
resin solution A-1 except that the amounts of the raw materials
shown in Table 2 introduced were changed.
TABLE-US-00002 TABLE 2 Example of Example of Example of Example of
Example of Example of Example of Production 7 Production 8
Production 9 Production 10 Production 11 Production 12 Production
13 Hydroxyl group containing resin B-1 B-2 B-3 B-4 B-5 B-6 B-7 for
paint purposes Initial Xylene 32.9 32.9 32.9 32.9 32.9 32.9 32.5
Introduction Drip-feed 2-Ethylhexyl 11.0 5.0 9.8 30.4 1.2 25.5
Component methacrylate Butyl acrylate 3.6 3.6 2-Hydroxyethyl 7.4
acrylate 2-Hydroxyethyl 15.8 8.5 13.8 5.6 5.3 5.3 methacrylate
2-Hydroxypropyl 5.5 2.9 12.5 29.5 17.2 methacrylate
t-Butylperoxy-2- 5.0 5.0 5.0 5.0 5.0 5.0 5.0 ethylhexanoate
Supplementary t-Butylperoxy-2- 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Catalyst
ethylhexanoate Xylene 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Supplementary
.epsilon.-Caprolactone 24.0 40.0 24.0 24.0 24.0 12.0 53.0 Component
Xylene 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Total 100.0 100.0 100.0 100.0
100.0 100.0 100.0 Resin hydroxyl group value 150 80 180 40 230 150
60 (mgKOH/g) Involatile fraction (%) 65.1 65.1 65.1 65.1 65.1 65.1
65.5 Weight average molecular weight 5200 5200 5200 5200 5200 5200
5200 Lactone compound structural unit 36.9 61.4 36.9 36.9 36.9 18.4
80.9 content in resin solid fraction (mass %)
Examples of Production 14 to 32
Production of Clear Paints CC-1 to CC-19
[0089] The raw materials shown in Tables 3 and 4 were mixed
sequentially and stirred until uniform mixtures were obtained to
prepare clear paints.
TABLE-US-00003 TABLE 3 Ex. of Ex. of Ex. of Ex. of Ex. of Ex. of
Ex. of Prod. Prod. Prod. Prod. Prod. Prod. Prod. 14 15 16 17 18 19
20 CC-1 CC-2 CC-3 CC-4 CC-5 CC-6 CC-7 A-1 60 60 80 20 60 A-2 60 A-3
60 A-4 A-5 A-6 B-1 40 40 20 80 B-2 40 B-3 40 40 B-4 B-5 B-6 B-7
Crosslinking agent 41 34.9 41 41 43.4 46.1 44.5 Desmodure N3200
Crosslinking agent 15 Yuban SE-60 Ultraviolet absorber 7 7 7 7 7 7
7 solution Photo-stabilizer 7 7 7 7 7 7 7 solution Surface
controlling 2 2 2 2 2 2 2 agent solution Sorbesso 100 15 15 15 15
15 15 15 TOTAL 172 180.9 172 172 174.4 177.1 175.5 Total hydroxyl
group 210 210 210 210 222 236 228 value Resin A A-1 A-1 A-1 A-1 A-1
A-2 A-3 Resin B B-1 B-1 B-1 B-1 B-3 B-2 B-3 Resin A/Resin B mass
60/40 60/40 80/20 20/80 60/40 60/40 60/40 ratio Isocyanate 100/0
80/20 100/0 100/0 100/0 100/0 100/0 compound/melamine resin mass
ratio Hydroxyl group value 250 250 250 250 250 340 260 of resin A
Hydroxyl group value 150 150 150 150 180 80 180 of resin B Amount
of caprolactone 16.6 16.6 16.6 16.6 16.6 18.4 24.0 structural units
in resin A (mass %) Amount of caprolactone 36.9 36.9 36.9 36.9 36.9
61.4 36.9 structural units in resin B (mass %)
TABLE-US-00004 TABLE 4 Ex. of Ex. of Ex. of Ex. of Ex. of Ex. of
Ex. of Ex. of Ex. of Ex. of Ex. of Ex. of Prod. Prod. Prod. Prod.
Prod. Prod. Prod. Prod. Prod. Prod. Prod. Prod. 21 22 23 24 25 26
27 28 29 30 31 32 CC-8 CC-9 CC-10 CC-11 CC-12 CC-13 CC-14 CC-15
CC-16 CC-17 CC-18 CC-19 A-1 100 60 60 60 60 60 A-2 60 A-3 60 A-4 60
A-5 60 A-6 60 B-1 100 40 40 40 B-2 B-3 40 B-4 40 B-5 40 40 B-6 40
B-7 40 40 Crosslinking agent 41 41 24.6 32.4 47.3 41 41 57.8 35.2
34 31.6 98.7 Desmodure N3200 Crosslinking agent 27.3 Yuban SE-60
Ultraviolet absorber 7 7 7 7 7 7 7 7 7 7 7 7 solution
Photo-stabilizer 7 7 7 7 7 7 7 7 7 7 7 7 solution Surface
controlling 2 2 2 2 2 2 2 2 2 2 2 2 agent solution Sorbesso 100 15
15 15 15 15 15 15 15 15 15 15 15 TOTAL 172 172 182.9 163.4 178.3
172 172 188.8 166.2 165 162.6 229.7 Total hydroxyl group 210 210
210 166 242 210 174 296 180 162 210 312 value Resin A A-1 -- A-1
A-1 A-1 A-1 A-1 A-2 A-3 A-4 A-6 A-5 Resin B -- B-1 B-1 B-4 B-5 B-6
B-7 B-5 B-7 B-3 B-1 B-1 Resin A/Resin B mass 100/0 0/100 60/40
60/40 60/40 60/40 60/40 60/40 60/40 60/40 60/40 60/40 ratio
Isocyanate 100/0 100/0 60/40 100/0 100/0 100/0 100/0 100/0 100/0
100/0 100/0 100/0 compound/melamine resin mass ratio Hydroxyl group
value 250 -- 250 250 250 250 250 340 260 150 250 420 of resin A
Hydroxyl group value -- 150 150 40 230 150 60 230 60 180 150 150 of
resin B Amount of caprolactone 16.6 -- 16.6 16.6 16.6 16.6 16.6
18.4 24 10 33 15 structural units in resin A (mass %) Amount of
caprolactone -- 36.9 36.9 36.9 36.9 18.4 80.9 36.9 80.9 36.9 36.9
36.9 structural units in resin B (mass %) << Notes for the
Tables >> 1) Desmodure N3200: Trade name, biuret type resin
of liquid HDI (involatile fraction 100 mass %, NCO content 23 mass
%), produced by the Sumica Beyer Urethane Co. 2) Yuban 20ES-60:
Trade name, melamine resin solution (involatile fraction 60 mass
%), produced by the Mitsui Kagaku Co. 3) Ultraviolet Absorber
Solution: Trade name Tinuvin 900, a 20 mass % xylene solution,
produced by the Ciba Specialty Chemicals Co. 4) Photo-stabilizer
Solution: Trade name Tinuvin 292, a 20 mass % xylene solution,
produced by the Ciba Specialty Chemicals Co. 5) Surface Controlling
Agent Solution: Trade name BYK-300, a 10 mass % xylene solution,
produced by the Bikkukemi Co. 6) Sorbesso 100: Trade name, aromatic
petroleum naphtha, produced by the Esso Co.
Examples 1 to 7
Production of Test Specimens and Investigation of Paint Film
Performance
[0090] The cationic electro-deposition paint Aqua No. 4200 (trade
name, produced by the BASF Coatings Japan Co.) was
electro-deposition painted so as to provide a dry film thickness of
20 .mu.m on a zinc phosphate treated mild steel sheet and baked for
25 minutes at 175.degree. C. and then the mid-coat paint HS-H300
(trade name, produced by the BASF Coatings Japan Co.) was air-spray
painted so as to provide a dry film thickness of 30 .mu.m and baked
for 30 minutes at 140.degree. C. Then Belcoat No. 6000 Black (trade
name, produced by the BASF coatings Japan Co., paint color: black)
which is a solvent-based base-coat paint was air-spray painted in
such a way as to provide a dry film thickness of 15 .mu.m and,
after setting for 3 minutes at 20.degree. C., the clear paints CC-1
to CC-7 diluted with Sorbesso 100 (trade name, produced by the Esso
Co., aromatic petroleum naphtha) to the painting viscosity (Ford
cup No. 4, 25 seconds at 20.degree. C.) were each air-spray painted
with a wet-on-wet system in such a way as to provide a dry film
thickness of 40 .mu.m and baked at 140.degree. C. for 30 minutes to
produce test specimens.
[0091] However, in the case of all of Examples 1 to 7, for the
staining resistance test sheets only, the base-coat paint was
replaced by Belcoat No. 6000 White (trade name, produced by the
BASF coatings Japan Co., paint color: white).
[0092] The paint film performance test results are shown in Table 5
and in all cases no paint turbidity arose and paint films with a
uniform gloss were obtained, and they exhibited excellent
appearance, car-wash scratching resistance, acid resistance,
staining resistance, water resistance and weather resistance.
TABLE-US-00005 TABLE 5 Example 1 Example 2 Example 3 Example 4
Example 5 Example 6 Example 7 CC-1 CC-2 CC-3 CC-4 CC-5 CC-6 CC-7
Appearance .largecircle. .largecircle. .largecircle. .largecircle.
.largecircle. .largecircle. .largecircle. Hardness .largecircle.
.largecircle. .largecircle. .largecircle. .largecircle.
.largecircle. .largecircle. Car-wash Damage Resistance 4.6 5.3 5.0
4.3 4.8 5.8 3.9 Acid Resistance .largecircle. .largecircle.
.largecircle. .largecircle. .largecircle. .largecircle.
.largecircle. Staining Resistance .largecircle. .largecircle.
.largecircle. .largecircle. .largecircle. .largecircle.
.largecircle. Water Resistance 0.2 0.3 0.4 0.3 0.3 0.2 0.5 Weather
Resistance No No No No No No No Abnormality Abnormality Abnormality
Abnormality Abnormality Abnormality Abnormality Resin A A-1 A-1 A-1
A-1 A-1 A-2 A-3 Resin B B-1 B-1 B-1 B-1 B-3 B-2 B-3 Resin A/B Mass
Ratio 60/40 60/40 80/20 20/80 60/40 60/40 60/40 Isocyanate 100/0
80/20 100/0 100/0 100/0 100/0 100/0 compound/melamine resin mass
ratio Hydroxyl group value of 250 250 250 250 250 340 260 resin A
Hydroxyl group value of 150 150 150 150 180 80 180 resin B Amount
of caprolactone 16.6 16.6 16.6 16.6 16.6 18.4 24 structural units
in resin A (mass %) Amount of caprolactone 36.9 36.9 36.9 36.9 36.9
61.4 36.9 structural units in resin B (mass %)
Comparative Examples 1 to 12
Production of Test Specimens and Investigation of Paint Film
Performance
[0093] Test specimens were prepared in the same way as in Example 1
except that the clear paints CC-8 to CC-19 were used. The paint
film performance test results are shown in Tables 6 and 7.
TABLE-US-00006 TABLE 6 Comparative Comparative Comparative
Comparative Comparative Comparative Example 1 Example 2 Example 3
Example 4 Example 5 Example 6 CC-8 CC-9 CC-10 CC-11 CC-12 CC-13
Appearance .largecircle. .largecircle. .largecircle. .largecircle.
.DELTA. .largecircle. Hardness .largecircle. .DELTA. .largecircle.
.largecircle. .largecircle. .largecircle. Car-wash Damage
Resistance 16.4 14.8 22.3 15.8 18.7 20.1 Acid Resistance
.largecircle. .DELTA. X .largecircle. .largecircle. .largecircle.
Staining Resistance .largecircle. .DELTA. .largecircle. .DELTA.
.largecircle. .largecircle. Water Resistance 0.3 1.2 0.3 0.7 0.2
0.3 Weather Resistance No No No No No No Abnormality Abnormality
Abnormality Abnormality Abnormality Abnormality Resin A A-1 -- A-1
A-1 A-1 A-1 Resin B -- B-1 B-1 B-4 B-5 B-6 Resin A/B Mass Ratio
100/0 0/100 60/40 60/40 60/40 60/40 Isocyanate 100/0 100/0 60/40
100/0 100/0 100/0 compound/melamine resin mass ratio Hydroxyl group
value of 250 -- 250 250 250 250 resin A Hydroxyl group value of --
150 150 40 230 150 resin B Amount of caprolactone 16.6 -- 16.6 16.6
16.6 16.6 structural units in resin A (mass %) Amount of
caprolactone -- 36.9 36.9 36.9 36.9 18.4 structural units in resin
B (mass %)
TABLE-US-00007 TABLE 7 Comparative Comparative Comparative
Comparative Comparative Comparative Example 7 Example 8 Example 9
Example 10 Example 11 Example 12 CC-14 CC-15 CC-16 CC-17 CC-18
CC-19 Appearance .DELTA. X X .largecircle. .largecircle. .DELTA.
Hardness .DELTA. .largecircle. X .DELTA. .DELTA. .largecircle.
Car-wash Damage Resistance 5.6 20.2 5.4 6.3 6.8 16.2 Acid
Resistance .DELTA. .largecircle. X .largecircle. .DELTA.
.largecircle. Staining Resistance .DELTA. .largecircle. .DELTA. X
.DELTA. .largecircle. Water Resistance 1.4 0.4 1.3 0.5 1 0.5
Weather Resistance No No No No No No Abnormality Abnormality
Abnormality Abnormality Abnormality Abnormality Resin A A-1 A-2 A-3
A-4 A-6 A-5 Resin B B-7 B-5 B-7 B-3 B-1 B-1 Resin A/B Mass Ratio
60/40 60/40 60/40 60/40 60/40 60/40 Isocyanate 100/0 100/0 100/0
100/0 100/0 100/0 compound/melamine resin mass ratio Hydroxyl group
value of 250 340 260 150 250 420 resin A Hydroxyl group value of 60
230 60 180 150 150 resin B Amount of caprolactone 16.6 18.4 24 10
33 15 structural units in resin A (mass %) Amount of caprolactone
80.9 36.9 80.9 36.9 36.9 36.9 structural units in resin B (mass
%)
* * * * *